According to a study in the Journal of Investigative Dermatology, exposure to air and particle pollution significantly correlates to an increase in signs of skin aging.

How? Air pollution contains microscopic contaminants, called polycyclic aromatic hydrocarbons (PAHs), which help produce Reactive Oxygen Species (ROS), or "free radicals." These strip the skin of barrier lipids, which help retain moisture and keep out dirt and other impurities. A compromised skin barrier can lead to increased skin sensitivity, discomfort and premature signs of skin aging, especially pigmentation issues.

The good news is that the skin – when healthy – is a pretty efficient filter of what's good versus what's bad on its own. But there are steps you can take to keep it healthy, smooth and even-toned in the face of pollution:

Do the Dermalogica Double Cleanse.
Using a clean, soft cloth helps get more dirt and grime off your skin, but for a professional level of clean, the Dermalogica Double Cleanse is a must! Start with PreCleanse, rinse, then apply your favorite Dermalogica Cleanser, rinse again, and voilà!

Smooth away the day
Add an anti-pollution powder exfoliant like Daily Superfoliant™ to your evening regimen. It helps detoxify pores and prevent the adherence of skin-aging pollutants for firmer, healthier-looking skin.

Pile on the antioxidants.
In general, pollution weakens your skin. Antioxidants, along with peptides and vitamins, help strengthen the skin and neutralize the primary triggers of skin aging. Look for products that contain ingredients like antioxidant White Tea, as well as microencapsulated vitamins A, C and E (all antioxidants).

Don't forget sunscreen!
Just because you're protecting your skin from pollution doesn't mean you should skimp on sunscreen. UV rays are still a top contributor to signs of skin aging, so wear an SPF30 or higher daily.